Lifting device supported at both ends and screw activated



' Nov. 19, 1968 A. GLASSMAN 3,411,749

G DEVICE SUPPORTED DS AND A LIFTIN AT BOTH CTUATED Filed Oct. 13, 1965 2 Sheets-Sheet 1 INVENTOR.

1963 A. GLASSMAN LIFTING DEVICE SUPPORTED AT BOTH ENDS AND SCREW ACTUATED Flled Oct 13 196.,

2 Sheets-Sheet 2 I INVENTOR. 4004/ 60mm United States Patent .0

3,411,749 LIFTING DEVICE SUPPORTED AT BOTH ENDS AND SCREW ACTIVATED 1 Aaron Glassman, Scranton, Pa., assiguor to Pennsylvania Sewing Research Corp., a corporation of Pennsylvania Filed Oct. 13, 1965, Ser. No. 495,419

4 Claims. (Cl. 254-100) ABSTRACT OF THE DISCLOSURE A lifting device comprised of an externally-threaded standard, adjustable in length, for spanning the underside of a table top and the floor below, and including anchor means at both ends to engage said underside and said floor and to maintain the standard in a substantially upright position. The device includes a sleeve slidably mounted and rotatable on the standard, a workholder mounted on the sleeve and shiftable radially from the standard, and internally-threaded means threaded on the standard for raising and lowering the sleeve.

This invention relates to a novel lifting device. This device is particularly usable for removing and/ or installing a motor on its mounting under a sewing machine.

It is frequently necessary to remove a defective motor from its mounting under a sewing machine table and to install a usable motor in its place. Because of the awkward position of the motor in addition to its weight, it is diflicult for one man to do this. Nevertheless, many factories have only one man available for this purpose.

An object of this invention is to provide a novel lifting device.

A further object is to provide a lifting device for removing 'and/ or installing a motor in its mounting under a work table.

Another object is to provide a lifting device with which one man can quickly and easily remove and/or install a motor in its mounting under a sewing machine table.

The novel lifting device, which is adapted to be used between the underside of a table top and the floor below, comprises (a) An externally threaded standard for spanning said underside andsaid floor,

(b) A sleeve slidably mounted on said standard and rotatable thereon,

(c) A work holder mounted on said sleeve,

(d) And an internally-threaded elevation adjustment means threaded on the standard for raising and lowering the sleeve.

To operate the novel device the standard is mounted in a substantially vertical position by engaging the table underside and the floor below. To this end, it is desirable and it is a further feature of a preferred form of the device, that the standard be adjustable in length, in which case, the standard may be positioned and then lengthened so that the ends of the standard engage the table underside and the floor. It is also desirable, and it is another feature of a preferred form of the device, that the standard have anchor means, such as conical points, at both ends thereof to prevent lateral movement of the standard, particularly when there is a heavy object in the work holder.

To remove a motor from its mounting, the elevation adjustment means is rotated to lower the sleeve and the work holder, which are then rotated about the standard until the work holder is below the motor to be removed. It is a feature of the preferred form of the device that the sleeve have a horizontally-extending arm, so designed that 3,411,749 Patented Nov. 19, 1968 ice the work holder may be positioned along the length of' the arm. I

The elevation adjustment means is now rotated to raise the sleeve and the work holder until the work holder lifts the motor clear of its mounting. The sleeve and work holder are now rotated about the standard to a position out from under the table. The motor may now be lifted off the work holder by hand or may be lowered into another Work holder by rotating the elevation adjustment means. To install a motor, the same steps are performed in reverse order after the standard has been positioned.

A further description of the device including a preferred embodiment thereof will now be given with reference to the drawing in which:

FIGURE 1 is a sectional elevational view of a first form of the device,

FIGURE 2 is a fragmentary sectional view along section lines 2-2 of FIGURE 1, and

FIGURE 3 is a fragmentary perspective view of a second form of the device.

A first form of the device illustrated in FIGURES 1 and 2 comprises a standard including an externally-threaded shaft 11. The standard includes an internally-threaded length adjustment member 12 that is threaded on the upper end of the shaft 11. The standard 11 may be adjusted in length by rotating the member 12 with respect to the shaft 11. The standard has conical points 13 and 14 at both ends thereof. The points 13 and 14 are adapted to engage the underside of a table top 15 and the floor 16 below the top 15 and to anchor the standard in a substantially upright position. An internally-threaded elevation adjustment means 17 is threaded on the shaft 11. The elevation adjustment means is intended to be rotated manually so that its position on the shaft 11 may be changed. As illustrated in FIGURE 1, the elevation adjustment means 17 is a spur gear which has been internally threaded. As illustrated in FIGURE 3, the elevation adjustment means is a large winged nut.

A sleeve 18 is slidably mounted on the shaft 11 and rests upon the elevation adjustment means 18. The sleeve is somewhat smaller than the elevation adjustment means 17. Since the sleeve 18 is slidably mounted, it is rotatable about the shaft 11. An arm 19 is welded to the sleeve 18 and extends outward horizontally. The arm 19 shown in detail in FIGURE 2 is comprised of a pair of metal straps 20 and 21 spaced by spacers 22 and 23. A work holder 24 is mounted on the arm 19 with a bolt 25 extending through the slot between the straps 20 and 21 and a pair of washers 26 and 27. The work holder 24 may be positioned along the arm 19 by loosening the bolt 25, sliding the work holder 24 to the desired position and then tightening the bolt 25. Also, the work holder 24 may be rotated about the bolt 25.

To operate the first form of the device to unload a motor, the standard is held in an upright position and the lengthening means 12 is rotated with respect to the shaft 11 until the points 13 and 14 anchor in the underside of a table top 15 and the floor 16 below. The bolt 25 is loosened and the elevation adjustment means 17 is rotated until the work holder 24 is below the motor to be unloaded. The arm 19 is rotated about the shaft 11 until it is under the motor. Then the work holder 24 is slid along the arm 19 and rotated about the bolt 25 until it is in a position to receive the motor. Then, the elevation adjustment means 17 is rotated to raise the work holder 24 .until it lifts the motor off of its mounting. The motor is indicated by the dotted circle 28.

To operate the device to install a motor, the standard is anchored in an upright position as described above.

Then the work holder 24 is placed in approximately the desired position on the arm 19 which is in a position above the motor mounting. The work holder 24 is rotated out from under the table. Then a motor is placed in the work (e) anchor means at both ends of said standard adapted to engage said underside and said floor and to maintain said standard in a substantially upright position.

2. A portable lifting device adapted to be used between holder 24. The work holder 24 is rotated back under the 5 the underside of a table top and the floor below said table table top and raised by rotating the elevation adjustment means 17 until the motor is in its mounting. After the motor has been mounted, the work holder 24 is lowered and then swung out from under the table top 15.

A fragmentary view of a second form of the device illustrated in FIGURE 3 comprises a standard 11a including a length adjustment member (not shown) and having conical points (not shown) at both ends thereof similar to those illustrated in FIGURE 1. The second form also includes an elevation adjustment means 17a and a round sleeve 18a similar to those illustrated in FIGURE 1. The second form has a square sleeve 28 held to the round sleeve 18a by a weld 29. An arm 19a of square crosssection fits loosely through the square sleeve 28. A work holder 24a is held to one end of the arm 19a with a fastener 25a which passes through an asymmetrically-located hole in the base plate of the work holder 24a and a hole near the one end of the arm 19a.

It has been found desirable to provide a set screw 31 in a wall of the square sleeve 28 so that, if desired, the arm 19a may be temporarily fixed in position in the square sleeve 28. It has also been found desirable to tilt the square sleeve 28 so that the work holder end of the arm 19a is somewhat higher than the other end of the arm 19a during operation of the device.

The operation of the second form of the device is similar to that of the first form except the work holder 24a may be positioned as desired simply by sliding the arm 19a in the square sleeve 28, rotating the work holder 24a about the bolt 25a, and rotating the round sleeve 18a about the standard 11a.

The novel lifting device may be varied in specific detail without departing from the essence of the invention. Thus, the standard may vary in design. A circular shaft about 28 inches long and about 1.0 inch in diameter is preferred. The standard is preferably externally threaded with National coarse threads. Similarly, the anchor means 13 and 14, the elevation adjustment means 17, the sleeve 18, the arm 19, and the work holder 24 may be modified in design.

The novel lifting device may be used in other ways than that described. For example, items other than motors may be handled and the tables may be for sewing or for other operations. Also, for example, when anchoring the standard in the upright position, the lower end of the standard may be anchored in a cross brace for the table legs and not in the floor. Such a mounting has the advantage that the standard remains upright should the table slide on the floor or be lifted.

What is claimed is:

1. A lifting device adapted to be used between the underside of a table top and the floor below said table top comprising:

(a) an externally-threaded standard for spanning said underside and said floor, said standard being adjustable in length,

(b) a sleeve slidably mounted on said standard and rotatable thereon,

(c) a work holder mounted on said sleeve and shiftable radially from said standard,

((1) an internally-threaded means threaded on said standard for raising and lowering said sleeve, and

top comprising:

(a) an externally-threaded standard for spanning said underside and said floor, said standard including an internally-threaded member threaded on one end of said standard and adapted to adjust the length of said standard by the rotation of one with respect to the other,

(b) a sleeve slidably mounted on said standard and rotatable thereon, said sleeve having a horizontallyextending arm,

(0) a work holder mounted on said arm and shiftable radially from said standard,

((1) an internally-threaded means threaded on said standard for raising and lowering said sleeve, and

(e) anchor means at both ends of said standard adapted to engage said underside and said floor and to maintain said standard in a substantially upright position.

3. The device described in claim 2 wherein the means for mounting said work holder on said sleeve comprises another sleeve of square cross-section fixedly attached to said first-mentioned sleeve, a horizontally-extending arm slidably mounted through said other sleeve, and a fastener engaging said work holder and one end of said arm, said work holder being rotatable about said fastener.

4. A portable lifting device adapted to be used between the underside of a table top and the floor below said table top comprising:

(a) an externally-threaded standard for spanning said underside and said floor, said standard including an internally-threaded member threaded on one end of said standard and adapted to adjust the length of said standard by the rotation of one with respect to the other,

(b) a sleeve slidably mounted on said standard and rotatable thereon, said sleeve having a horizontallyextending arm, said arm having a vertical slot extending radially from said sleeve,

(0) a Work holder mounted on said arm including a fastener engaging said work holder and extending through said slot, said work holder being shiftable radially from said standard along the radial dimension of said slot,

(d) an internally-threaded means threaded on said standard adapted to receive thereon the weight of said sleeve and to raise and lower said sleeve by the rotation of said means with respect to said standard, and

(e) a conical point at both ends of said standard adapted to engage said underside and said floor and to anchor said standard in a substantially upright position.

References Cited UNITED STATES PATENTS 234,105 11/1880 Wollet 254-101 1,576,383 3/1926 Walker 254- 1,912,475 6/1933 Countryman 254-133 1,916,476 7/1933 Harbaugh et al 254-133 2,663,929 12/ 1953 Carpenter 269-59 FOREIGN PATENTS 684,845 12/ 1952 Great Britain.

OTHELL M. SIMPSON, Primary Examiner. 

